基于DDS技术正弦波信号发生器的设计  

Design of sine wave signal generator based on DDS technology

作　　者：汉泽西[1] 张海飞[1] 王文渤 李国栋[1] 

机构地区：[1]西安石油大学电子工程学院,西安710065 [2]兰州石油化工工程公司,兰州730060

出　　处：《电子测试》2009年第8期65-69,77,共6页Electronic Test

摘　　要：介绍了直接数字频率合成(DDS)的原理,依据其基本原理提出一种基于单片机STC89C52控制直接数字频率合成芯片AD9851产生频率可调的正弦波信号发生器的电路设计。通过键盘输入所需频率值,单片机通过响应键盘中断将其输入频率转换为频率控制字,并将其写入AD9851。AD9851产生的正弦波信号经低通滤波得到纯正的正弦波信号,最后经过功率放大器输出至负载。经实验表明该系统可产生频率在1Hz～10MHz,精度为0.1Hz,峰值为5V的正弦波信号,且易于操纵,输出稳定。This paper introduces the basic principles of Direct Digital Synthesis（DDS） and a design method of sine wave generator the frequency which can be changed. The STC89C52 CPU can control the DDS chip to produce different frequency of sinusoid via by adjusting different frequency words. Keyboard is used to input the frequency value. STC89C52 respond to the interrupt of the keyboard. Then it will convert the frequency value to a frequency word and send it to AD9851. The frequency of sinusoid will be exported by AD9851. After a low pass filter, a pure sine wave can be obtain and is droved by a power amplifier to output. Experiments show that the system can produce the sine wave which is characterized by frequency 1Hz to 10MHz, an accuracy of 0. 1Hz, the amplitude of signal to 5V. It is easy to manipulate and the output is stability.

关 键 词：信号发生器 直接数字频率合成 AD9851 

分 类 号：TN741[电子电信—电路与系统]